Increasing the safety of nuclear reactors and extending the life of nuclear fuel


The team found a new effective concept of Zr alloy nuclear fuel rod surface protection against degradation caused by both working and accidental temperatures oxidation by covering the outer surface of the nuclear fuel rod with a protective layer consisting of a polycrystalline diamond (PCD) layer. Carbon released from the PCD film enters the underlying Zr material and changes its properties, such that uptake of oxygen and hydrogen is significantly decreased. In the scope of common project (Technology Agency of the CR, TA04020156) with Westinghouse, USA it was proved that protective PCD layer reduced Zr nuclear fuel cladding oxidation at operating temperatures (by 30-50%), which prolongs the lifetime of the nuclear cladding and consequently enhances nuclear fuel burn-up.  PCD layer reduced Zr surface oxidation in hot steam at 900oC by 20% which prolongs the lifetime of the nuclear cladding at crucial accidental conditions. In 2016 US and European patents were applied and filled. In 2016 US and European patents were applied and filled. In 2020 and 2021 the European and US patents were awarded. Zirconium fuel elements coated with anti-corrosion PCD layers were selected by Westinghouse as potential candidates for Accident Tolerant Fuel. Team was also the first to prepare a double-layered coating consisting of an active (PCD) and passive (CrAlSiN) part as a protective element for Zr alloy surface against high-temperature oxidation in a hot water environment. Double-layer coatings reduce ZIRLO nuclear fuel tube oxidation by more than 88% compared to that of uncoated ZIRLO tubes treated for 4 days in 400 °C hot steam.  Czech patent was also awarded.

Discovery of the new way against corrosion protection of nuclear materials nuclear fuel rods by PCD coating was widely presented in the media (newspapers and TV) and highly appreciated by society (Scientists Help Safeguard Nuclear Reactors, Materials Performance, 2015), Innovation Origins

HN, LN, Technical Magazine, Reporter magazine